Recommendation engine: Downvote any game you've heard of before
This might be a slightly unusual attempt at a prompt, but might draw some appealing unusual options.
The way it goes: Suggest games, ideally the kind that you believe would have relatively broad appeal. Don't feel bad about downvotes, but do downvote any game that's suggested if you have heard of it before (Perhaps, give some special treatment if it was literally your game of the year). This rule is meant to encourage people to post the indie darlings that took some unusual attention and discovery to be aware of and appreciate.
If possible, link to the Steam pages for the games in question, so that anyone interested can quickly take a look at screenshots and reviews. And, as a general tip, anything with over 1000 steam reviews probably doesn't belong here. While I'd recommend that you only suggest one game per post, at the very most limit it to three.
If I am incorrect about downvotes being inconsequential account-wide, say so and it might be possible to work out a different system.
Rabbit and Steel - Cross between a bullet hell and roguelite with raid style gameplay. Requires very close co-ordination with your team to survive (up to 4 player co-op). Punishing but rewarding.
Surprised to see the downvotes (by which I mean, I'm surprised so many people know this, I'd never heard of it at all).
"Roguelike co-op game requiring close coordination" seems like a mega-fail by concept since I tend to think of co-op games as more relaxed. But, looking at gameplay videos, it reminds me of FFXIV raid mechanics in a simplified game format. I can see how that would appeal to some people.